Lecture #3: Gravity Waves in GCMs. Charles McLandress (Banff Summer School 7-13 May 2005)
|
|
- Jayson McGee
- 6 years ago
- Views:
Transcription
1 Lecture #3: Gravity Waves in GCMs Charles McLandress (Banff Summer School 7-13 May 2005) 1
2 Outline of Lecture 1. Role of GWs in the middle atmosphere 2. Background theory 3. Resolved GWs in GCMs 4. Parameterized GWs in GCMs 2
3 Part 1: The Role of Gravity Waves in the Middle Atmosphere keep mesosphere far from radiative equilibrium (e.g., cold summer mesopause and reversal of the mesospheric jets). alleviate cold bias in Southern Hemisphere winter polar stratosphere. help drive quasi-biennial oscillation (QBO) in tropical lower stratosphere. 3
4 Gravity waves seen in noctilucent clouds in mesosphere 4
5 Cold Summer Mesopause Observed Temperature (January) Cooling is due to adiabatic ascent in the summer pole that results from an eastward force exerted by breaking gravity waves: - the eastward force generates an eastward wind that is deflected toward the winter pole by the Coriolis force. - conservation of mass then implies ascent at the summer pole. 150K 220K Radiative Temperature (January) 5 from Fels (1987)
6 Observed zonal mean zonal winds in mesosphere 40S 40N Reversal of summer mesospheric winds 6
7 Alleviation of cold bias is SH winter polar stratosphere downwelling produced by mesospheric gravity wave drag extends into the stratosphere as a consequence of downward control and the long radiative timescales in the cold winter pole. without GWD this downwelling produces adiabatic warming as a result of compression of air parcels. this effect is more important in the SH where the effects of other waves (planetary Rossby waves and topographically generated gravity waves) are weaker. GCMs typically have a cold bias in the SH winter polar stratosphere, which is also referred to as the cold pole problem. with GWD (from Garcia & Boville, 1994) 7
8 Quasi-biennial oscillation an oscillation of the zonal mean zonal winds in the equatorial lower stratosphere with a period varying from 22 to 34 months. the QBO is a wave-driven phenomenon. the original theory proposed by Holton and Lindzen (1972) assumes that equatorial planetary waves provide the wave driving. Dunkerton (1997) showed that in the presence of tropical upwelling planetary waves were not enough; he proposed that gravity waves provided the additional wave driving. (Radiosonde observations from ) 8
9 Part 2: Background Theory 9
10 Buoyancy oscillations (Newton s 2nd Law) displaced parcel (hydrostatic basic state) (Ideal gas law and definition of potential temperature) (potential temperature of parcel is conserved) (for small vertical displacement) (buoyancy force) Parcel oscillates in the vertical with the buoyancy frequency N. 10
11 Internal gravity waves Now consider the parcel of air displaced upward along a sloping surface: Acceleration of parcel up the slope is t = 0 m Component of buoyancy force along the slope is k Newton s 2nd law gives which is the dispersion relation for a hydrostatic gravity wave in the Boussinesq approximation. 11
12 Linear gravity wave equations Equations governing hydrostatic gravity waves without rotation are: (zonal momentum equation) (thermodynamic equation) (mass continuity equation) Consider plane wave solutions: Resulting dispersion relation is: (intrinsic frequency) 12
13 Nonhydrostatic and rotational effects the previous example was for linear hydrostatic GWs without the effects of the Earth s rotation. a more general dispersion relation which accounts for nonhydrostatic and rotational effects is: where f is the Coriolis parameter. a vertically propagating wave (m real) now requires that 13
14 Vertically trapped mountain waves Mean wind direction (U) For a stationary mountain wave with Dispersion relation becomes Short horizontal wavelengths (k > N/U) are vertically trapped. Satellite image of vertically trapped mountain waves (courtesy of Sam Shen, U of Alta) 14
15 Momentum flux vertically propagating gravity waves transport momentum over large height ranges. consider the continuity equation for the hydrostatic gravity in the case where m << 2H: u X " " GWs with eastward (westward) intrinsic frequencies have positive (negative) momentum flux. 15
16 Momentum flux deposition gravity waves interact with the mean flow through the deposition of momentum: GWD for a steady, linear & undamped GW, the momentum flux is independent of height GWD = 0. " GWD arises when the momentum flux changes with height, which will occur if: 1. the GW approaches a critical level (c = U) 2. the GW breaks and undergoes turbulent dissipation. 16
17 Cartoon depicting critical level filtering and nonlinear breakdown of a monochromatic GW Mean wind Momentum flux GWD 17
18 Mesoscale model simulations of convectively generated GWs to simulate small-scale GWs generated by convection a 2D or 3D mesoscale model must be used. compared to a GCM a mesoscale model employs a very fine horizontal resolution (1km) and a short timestep (5 s). here we will examine results from a 3D simulation of a tropical squall line. the model equations are nonlinear, compressible, nonhydrostatic and nonrotating; cloud microphysics parameterization is used. 18
19 3D mesoscale model results 550 km From Piani and Durran (JAS 2001) QBO east Eastward propagating GWs filtered out by eastward QBO winds Height (km) Y (km) 40km QBO west Height (km) Y (km) 40km Westward propagating GWs filtered out by westward QBO winds X (km) W X (km) E 19
20 Satellite observations of convectively generated small-scale gravity waves Microwave Limb Sounder geometry Seasonal average (NH summer) Single day of temperature data McLandress et al (2000) Temperature variance strongest over convective regions 20
21 Part 3: Resolved Gravity Waves in GCMs 21
22 Kinetic energy spectra in middle atmosphere GCMs Rotational KE CMAM resolved GWs are included in the divergent part of the KE. all models show that divergent KE grows faster with height than the rotational KE. Divergent KE there are large differences in the amplitude of the spectra between models. CMAM Koshyk et al (1999) 22
23 precipitation Fz (70 hpa) Fz (1 hpa) Wavenumber-frequency spectra of precipitation and the vertical component of the EP flux for different GCMs 2D spectra of precipitation and vertically propagating waves in the tropics is closely tied to the type of convective parameterization that is used in the GCM. Horinouchi et al (JAS 2003) 23
24 Impact of model resolution on mesospheric mean winds 160 m/s 120 m/s -60 m/s -40 m/s zonal mean zonal winds for June-August from the SKYHI model for different horizontal resolutions. As the model resolution increases the speed of the mesospheric jets decrease: - higher resolution means more GWs are resolved. - more GWs mean more drag and weaker winds. from Hamilton (JATP 1996) 24
25 Resolved mesospheric gravity wave drag Eliassen-Palm flux divergence for June- August from the SKYHI model for different horizontal resolutions the magnitude of the EPFD increases as model resolution increases. From Hamilton (JATP 1996) 25
26 Part 4: Parameterized Gravity Waves in GCMs 26
27 the SKYHI model results demonstrated that a GCM with extremely high resolution is required to simulate the small-scale GWs that produce the required GWD in the mesosphere. this is further demonstrated by comparing the vertical flux of horizontal momentum from the low and high resolution simulations of SKYHI - the shallow slope means that very high horizontal resolution is required. Hamilton (1996) since such high resolution is currently not possible for a GCM the effects of these missing gravity waves must be parameterized. 27
28 Overview of the GWD parameterization problem the basic idea is to include the effects of GWD on the mean circulation without actually solving for the gravity waves. a GWD parameterization is built on ideas from linear gravity wave theory in conjunction with a mechanism for the nonlinear breakdown (i.e., dissipation) of GWs. gross simplifications are required in order that the parameterization be computationally efficient. all GWD parameterizations currently used in GCMs consist of three components: 1. Launch spectrum in the lower atmosphere 2. Linear propagation upward from the launch level 3. Nonlinear dissipation mechanism when waves attain large amplitudes. 28
29 1. Launch spectrum must specify a discrete or continuous spectrum of GWs at some level in the lower atmosphere which is assumed to lie above the actual gravity source regions. spectrum is a function of horizontal wavenumber and frequency. amplitude of waves in spectrum determine the amount of momentum flux they carry. great uncertainty in how to specify the launch spectrum since there are insufficient observations. a further complication is that waves with long vertical wavelengths (i.e., high intrinsic frequencies) are impossible to measure in the lower atmosphere: BUT these are the waves that have the greatest impact on the mesosphere. 29
30 2. Linear propagation current GWD parameterizations assume that GW propagation is straight up (i.e., no propagation into adjacent grid boxes). a linear dispersion relation is used to relate the various wave parameters (e.g., the dispersion relation for hydrostatic nonrotating GWs is often employed). a GW is assumed to propagate linearly, conserving its momentum flux until either: 1. a critical level is reached where c=u or 2. its amplitude exceeds a specified threshold. 30
31 3. Nonlinear dissipation mechanisms 1. Convective instability and saturation: Lindzen (1981) amplitude of GW increases to point where the total temperature lapse rate is convectively unstable. Small-scale turbulence damps the GW and maintains it at an amplitude of neutral stability. 2. Convective instability and obliteration: Alexander and Dunkerton (1999) Uses Lindzen s convective instability criterion but deposits all of the GWs momentum flux at the breaking height. 31
32 3. Doppler spreading: Hines (1991, 1993, 1997) a GW is dissipated as it reaches a critical level given by the background wind and the wind associated with the parameterized spectrum (i.e., c = U + u ). the term spreading is used since the Doppler shifting of the vertical wavenumber is defined only in a statistical sense. 4. Nonlinear diffusion: Weinstock (1982); Medvedev and Klaassen (1995) A complicated and virtually incomprehensible (to me at least) mechanism that we will discuss no more. 32
33 5. Empirical saturation condition: Warner and McIntyre (1986) The observed m -3 form of the observed spectrum is used to limit wave amplitudes 33
34 Simulations using the Canadian Middle Atmosphere Model (CMAM) the CMAM is a middle atmosphere GCM that extends from the ground to 100 km. horizontal resolution is T32 (about 5-6 deg). comprehensive set of physical parameterizations relevant to the troposphere and middle atmosphere. a single GWD parameterization that contains different nonlinear dissipation mechanisms. experiments all use identical launch spectrum for the parameterized GWs. McLandress and Scinocca (JAS, in press). 34
35 Filtering of GW spectrum by tropospheric winds Simulations using Hines Doppler spread parameterization: Strong reversal Strong westerlies Weak reversal Weak westerlies CL filtering by tropospheric westerlies 35
36 Simulations using different nonlinear dissipation mechanisms in the GWD parameterization Warner & McIntyre (1996) Modified Warner & McIntyre (1996) Hines Doppler spread With only critical level filtering important message here is that the different dissipation mechanisms can be made to produce nearly same GCM response by a simple scaling of the height at which momentum is deposited. this means that details of dissipation are not that important. 36
37 1D-QBO model results prescribed upwelling wave momentum flux Planetary waves (Holton & Lindzen, 1972) Small-scale gravity waves parameterized using Hines (1997) QBO is suppressed when upwelling is increased (only planetary waves). QBO reappears when gravity wave momentum flux is increased (both PWs and GWs). 37
38 73 km Pressure (hpa) 98 levels 30 km Simulating the QBO in the CMAM Zonal mean zonal winds at equator Month Pressure (hpa) 71 levels 96 km 30 km T47 horizontal resolution Warner and McIntyre GWD parameterization: - momentum flux enhanced by factor of four in tropics. 38 Month
39 The End 39
Non-orographic gravity waves in general circulation models
Non-orographic gravity waves in general circulation models Erich Becker Leibniz-Institute of Atmospheric Physics (IAP) Kühlungsborn, Germany (1) General problem and issues Assumed equilibirium state for
More informationLecture #2 Planetary Wave Models. Charles McLandress (Banff Summer School 7-13 May 2005)
Lecture #2 Planetary Wave Models Charles McLandress (Banff Summer School 7-13 May 2005) 1 Outline of Lecture 1. Observational motivation 2. Forced planetary waves in the stratosphere 3. Traveling planetary
More informationLecture #1 Tidal Models. Charles McLandress (Banff Summer School 7-13 May 2005)
Lecture #1 Tidal Models Charles McLandress (Banff Summer School 7-13 May 2005) 1 Outline of Lecture 1. Introduction 2. Brief description of tides 3. Observations of tides 4. Simulating tides using a general
More informationImproved middle atmosphere climate and forecasts in the ECMWF model through a non-orographic gravity wave drag parametrization
Improved middle atmosphere climate and forecasts in the ECMWF model through a non-orographic gravity wave drag parametrization April 2010 Andrew Orr*, Peter Bechtold, John Scinocca 1, Manfred Ern 2 and
More informationThe representation of non-orographic gravity waves in the IFS Part II: A physically based spectral parametrization. Andrew Orr. Research Department
593 The representation of non-orographic gravity waves in the IFS Part II: A physically based spectral parametrization Andrew Orr Research Department May 2009 Series: ECMWF Technical Memoranda A full list
More informationImproved middle atmosphere climate and forecasts in the ECMWF model through a nonorographic. parametrization
625 Improved middle atmosphere climate and forecasts in the ECMWF model through a nonorographic gravity wave drag parametrization Andrew Orr*, Peter Bechtold, John Scinocca 1, Manfred Ern 2 and Marta Janiskova
More informationDynamics and Kinematics
Geophysics Fluid Dynamics () Syllabus Course Time Lectures: Tu, Th 09:30-10:50 Discussion: 3315 Croul Hall Text Book J. R. Holton, "An introduction to Dynamic Meteorology", Academic Press (Ch. 1, 2, 3,
More informationAngular momentum conservation and gravity wave drag parameterization: implications for climate models
Angular momentum conservation and gravity wave drag parameterization: implications for climate models Article Published Version Shaw, T. A. and Shepherd, T. G. (2007) Angular momentum conservation and
More informationGeophysics Fluid Dynamics (ESS228)
Geophysics Fluid Dynamics (ESS228) Course Time Lectures: Tu, Th 09:30-10:50 Discussion: 3315 Croul Hall Text Book J. R. Holton, "An introduction to Dynamic Meteorology", Academic Press (Ch. 1, 2, 3, 4,
More informationHydrodynamic conservation laws and turbulent friction in atmospheric circulation models
Hydrodynamic conservation laws and turbulent friction in atmospheric circulation models Erich Becker Leibniz-Institute of Atmospheric Physics, Kühlungsborn, Germany Including contributions from Ulrike
More informationWave-driven equatorial annual oscillation induced and modulated by the solar cycle
GEOPHYSICAL RESEARCH LETTERS, VOL. 32, L20811, doi:10.1029/2005gl023090, 2005 Wave-driven equatorial annual oscillation induced and modulated by the solar cycle Hans G. Mayr, 1 John G. Mengel, 2 and Charles
More informationEffects of a convective GWD parameterization in the global forecast system of the Met Office Unified Model in Korea
Effects of a convective GWD parameterization in the global forecast system of the Met Office Unified Model in Korea Young-Ha Kim 1, Hye-Yeong Chun 1, and Dong-Joon Kim 2 1 Yonsei University, Seoul, Korea
More informationwarmest (coldest) temperatures at summer heat dispersed upward by vertical motion Prof. Jin-Yi Yu ESS200A heated by solar radiation at the base
Pole Eq Lecture 3: ATMOSPHERE (Outline) JS JP Hadley Cell Ferrel Cell Polar Cell (driven by eddies) L H L H Basic Structures and Dynamics General Circulation in the Troposphere General Circulation in the
More informationResponses of mesosphere and lower thermosphere temperatures to gravity wave forcing during stratospheric sudden warming
Click Here for Full Article GEOPHYSICAL RESEARCH LETTERS, VOL. 37,, doi:10.1029/2009gl042351, 2010 Responses of mesosphere and lower thermosphere temperatures to gravity wave forcing during stratospheric
More informationGravity Waves. Lecture 5: Waves in Atmosphere. Waves in the Atmosphere and Oceans. Internal Gravity (Buoyancy) Waves 2/9/2017
Lecture 5: Waves in Atmosphere Perturbation Method Properties of Wave Shallow Water Model Gravity Waves Rossby Waves Waves in the Atmosphere and Oceans Restoring Force Conservation of potential temperature
More informationNon-local Momentum Transport Parameterizations. Joe Tribbia NCAR.ESSL.CGD.AMP
Non-local Momentum Transport Parameterizations Joe Tribbia NCAR.ESSL.CGD.AMP Outline Historical view: gravity wave drag (GWD) and convective momentum transport (CMT) GWD development -semi-linear theory
More informationEliassen-Palm Theory
Eliassen-Palm Theory David Painemal MPO611 April 2007 I. Introduction The separation of the flow into its zonal average and the deviations therefrom has been a dominant paradigm for analyses of the general
More informationDynamical coupling between the middle atmosphere and lower thermosphere
Dynamical coupling between the middle atmosphere and lower thermosphere Anne Smith, Dan Marsh, Nick Pedatella NCAR* Tomoko Matsuo CIRES/NOAA NCAR is sponsored by the National Science Foundation Model runs
More informationA non-hydrostatic and compressible 2-D model simulation of Internal Gravity Waves generated by convection
Earth Planets Space, 51, 485 498, 1999 A non-hydrostatic and compressible 2-D model simulation of Internal Gravity Waves generated by convection Kenshi Goya and Saburo Miyahara Department of Earth and
More informationThe stratospheric response to extratropical torques and its relationship with the annular mode
The stratospheric response to extratropical torques and its relationship with the annular mode Peter Watson 1, Lesley Gray 1,2 1. Atmospheric, Oceanic and Planetary Physics, Oxford University 2. National
More informationThe Planetary Circulation System
12 The Planetary Circulation System Learning Goals After studying this chapter, students should be able to: 1. describe and account for the global patterns of pressure, wind patterns and ocean currents
More informationGoals of this Chapter
Waves in the Atmosphere and Oceans Restoring Force Conservation of potential temperature in the presence of positive static stability internal gravity waves Conservation of potential vorticity in the presence
More informationThe Scientific Value of Stratospheric Wind Measurements
Working Group on Space-based Lidar Winds, Monterey, 2008 The Scientific Value of Stratospheric Wind Measurements Ted Shepherd Department of Physics University of Toronto The distribution of ozone (important
More information1. The vertical structure of the atmosphere. Temperature profile.
Lecture 4. The structure of the atmosphere. Air in motion. Objectives: 1. The vertical structure of the atmosphere. Temperature profile. 2. Temperature in the lower atmosphere: dry adiabatic lapse rate.
More informationDepartment of Atmospheric Sciences, Yonsei University, Seoul, South Korea. National Center for Atmospheric Research, Boulder, Colorado
2286 J O U R N A L O F T H E A T M O S P H E R I C S C I E N C E S VOLUME 64 Momentum Flux Spectrum of Convectively Forced Internal Gravity Waves and Its Application to Gravity Wave Drag Parameterization.
More information196 7 atmospheric oscillations:
196 7 atmospheric oscillations: 7.4 INTERNAL GRAVITY (BUOYANCY) WAVES We now consider the nature of gravity wave propagation in the atmosphere. Atmospheric gravity waves can only exist when the atmosphere
More information1/27/2010. With this method, all filed variables are separated into. from the basic state: Assumptions 1: : the basic state variables must
Lecture 5: Waves in Atmosphere Perturbation Method With this method, all filed variables are separated into two parts: (a) a basic state part and (b) a deviation from the basic state: Perturbation Method
More informationFour ways of inferring the MMC. 1. direct measurement of [v] 2. vorticity balance. 3. total energy balance
Four ways of inferring the MMC 1. direct measurement of [v] 2. vorticity balance 3. total energy balance 4. eliminating time derivatives in governing equations Four ways of inferring the MMC 1. direct
More informationCHAPTER 4. THE HADLEY CIRCULATION 59 smaller than that in midlatitudes. This is illustrated in Fig. 4.2 which shows the departures from zonal symmetry
Chapter 4 THE HADLEY CIRCULATION The early work on the mean meridional circulation of the tropics was motivated by observations of the trade winds. Halley (1686) and Hadley (1735) concluded that the trade
More informationNOTES AND CORRESPONDENCE. Characteristics and Momentum Flux Spectrum of Convectively Forced Internal Gravity Waves in Ensemble Numerical Simulations
OCTOBER 2007 N O T E S A N D C O R R E S P O N D E N C E 3723 NOTES AND CORRESPONDENCE Characteristics and Momentum Flux Spectrum of Convectively Forced Internal Gravity Waves in Ensemble Numerical Simulations
More informationAssessing the impact of gravity waves on the tropical middle atmosphere in a General Circulation Model
Assessing the impact of gravity waves on the tropical middle atmosphere in a General Circulation Model AGU Chapman Conference on Atmospheric Gravity Waves Andrew C Bushell, David R Jackson, Glenn J Shutts,
More informationPart-8c Circulation (Cont)
Part-8c Circulation (Cont) Global Circulation Means of Transfering Heat Easterlies /Westerlies Polar Front Planetary Waves Gravity Waves Mars Circulation Giant Planet Atmospheres Zones and Belts Global
More informationA Method of Specifying the Gravity Wave Spectrum above Convection Based on Latent Heating Properties and Background Wind
34 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME 61 A Method of Specifying the Gravity Wave Spectrum above Convection Based on Latent Heating Properties and Background Wind JADWIGA H. BERES National Center
More informationNWP Equations (Adapted from UCAR/COMET Online Modules)
NWP Equations (Adapted from UCAR/COMET Online Modules) Certain physical laws of motion and conservation of energy (for example, Newton's Second Law of Motion and the First Law of Thermodynamics) govern
More informationAn Introduction to Coupled Models of the Atmosphere Ocean System
An Introduction to Coupled Models of the Atmosphere Ocean System Jonathon S. Wright jswright@tsinghua.edu.cn Atmosphere Ocean Coupling 1. Important to climate on a wide range of time scales Diurnal to
More informationAnalysis and numerical study of inertia-gravity waves generated by convection in the tropics
University of Colorado, Boulder CU Scholar Atmospheric & Oceanic Sciences Graduate Theses & Dissertations Atmospheric & Oceanic Sciences Spring 1-1-2011 Analysis and numerical study of inertia-gravity
More informationComparing QBO and ENSO impacts on stratospheric transport in WACCM-SD and -FR
Comparing QBO and ENSO impacts on stratospheric transport in WACCM-SD and -FR Multivariate ENSO Index + QBO shear index based on Singapore wind U50-U25 CESM Chemistry WG Meeting Boulder, CO February 10,
More informationOn the Wave Spectrum Generated by Tropical Heating
2042 J O U R N A L O F T H E A T M O S P H E R I C S C I E N C E S VOLUME 68 On the Wave Spectrum Generated by Tropical Heating DAVID A. ORTLAND NorthWest Research Associates, Redmond, Washington M. JOAN
More informationStratospheric Predictability and the Arctic Polar-night Jet Oscillation
Stratospheric Predictability and the Arctic Polar-night Jet Oscillation Peter Hitchcock1, Ted Shepherd2 University of Toronto Now at Cambridge 2Now at Reading 1 Gloria Manney JPL, NMT, Now at NWRA NAM
More informationA mechanistic model study of quasi-stationary wave reflection. D.A. Ortland T.J. Dunkerton NorthWest Research Associates Bellevue WA
A mechanistic model study of quasi-stationary wave reflection D.A. Ortland T.J. Dunkerton ortland@nwra.com NorthWest Research Associates Bellevue WA Quasi-stationary flow Describe in terms of zonal mean
More informationA statistical study of gravity waves from radiosonde observations at Wuhan (30 N, 114 E) China
Annales Geophysicae, 23, 665 673, 2005 SRef-ID: 1432-0576/ag/2005-23-665 European Geosciences Union 2005 Annales Geophysicae A statistical study of gravity waves from radiosonde observations at Wuhan (30
More informationHEIGHT-LATITUDE STRUCTURE OF PLANETARY WAVES IN THE STRATOSPHERE AND TROPOSPHERE. V. Guryanov, A. Fahrutdinova, S. Yurtaeva
HEIGHT-LATITUDE STRUCTURE OF PLANETARY WAVES IN THE STRATOSPHERE AND TROPOSPHERE INTRODUCTION V. Guryanov, A. Fahrutdinova, S. Yurtaeva Kazan State University, Kazan, Russia When constructing empirical
More informationGeneral Circulation. Nili Harnik DEES, Lamont-Doherty Earth Observatory
General Circulation Nili Harnik DEES, Lamont-Doherty Earth Observatory nili@ldeo.columbia.edu Latitudinal Radiation Imbalance The annual mean, averaged around latitude circles, of the balance between the
More information2. Meridional atmospheric structure; heat and water transport. Recall that the most primitive equilibrium climate model can be written
2. Meridional atmospheric structure; heat and water transport The equator-to-pole temperature difference DT was stronger during the last glacial maximum, with polar temperatures down by at least twice
More informationChihoko Yamashita 1,2, Han-Li Liu 1
1 1 Gravity Waves and the High-Resolution Modeling (Using ECMWF-T799) Chihoko Yamashita 1,2, Han-Li Liu 1 1. NCAR/HAO 2. University of Colorado at Boulder AWMG/WAWG Workshop 2012-02-01 Motivations Gravity
More information3. Midlatitude Storm Tracks and the North Atlantic Oscillation
3. Midlatitude Storm Tracks and the North Atlantic Oscillation Copyright 2006 Emily Shuckburgh, University of Cambridge. Not to be quoted or reproduced without permission. EFS 3/1 Review of key results
More informationOliver Bühler Waves and Vortices
Oliver Bühler Waves and Vortices Four combined lectures Introduction, wave theory, simple mean flows Wave-driven vortex dynamics on beaches Three-dimensional gravity waves, recoil & capture Waves, vortices,
More informationF = ma. ATS 150 Global Climate Change Winds and Weather. Scott Denning CSU CMMAP 1. Please read Chapter 6 from Archer Textbook
Winds and Weather Please read Chapter 6 from Archer Textbook Circulation of the atmosphere and oceans are driven by energy imbalances Energy Imbalances What Makes the Wind Blow? Three real forces (gravity,
More informationInteractions Between the Stratosphere and Troposphere
Interactions Between the Stratosphere and Troposphere A personal perspective Scott Osprey Courtesy of Verena Schenzinger The Wave-Driven Circulation Global structure of Temperature and Wind Temperature
More information7 The General Circulation
7 The General Circulation 7.1 The axisymmetric state At the beginning of the class, we discussed the nonlinear, inviscid, axisymmetric theory of the meridional structure of the atmosphere. The important
More informationTraveling planetary-scale Rossby waves in the winter stratosphere: The role of tropospheric baroclinic instability
GEOPHYSICAL RESEARCH LETTERS, VOL. 39,, doi:10.1029/2012gl053684, 2012 Traveling planetary-scale Rossby waves in the winter stratosphere: The role of tropospheric baroclinic instability Daniela I. V. Domeisen
More informationA Spectral Parameterization of Drag, Eddy Diffusion, and Wave Heating for a Three-Dimensional Flow Induced by Breaking Gravity Waves
2520 J O U R N A L O F T H E A T M O S P H E R I C S C I E N C E S VOLUME 67 A Spectral Parameterization of Drag Eddy Diffusion and Wave Heating for a Three-Dimensional Flow Induced by Breaking Gravity
More informationDynamics of the Atmosphere. Large-scale flow with rotation and stratification
12.810 Dynamics of the Atmosphere Large-scale flow with rotation and stratification Visualization of meandering jet stream Upper level winds from June 10th to July 8th 1988 from MERRA Red shows faster
More information2. Outline of the MRI-EPS
2. Outline of the MRI-EPS The MRI-EPS includes BGM cycle system running on the MRI supercomputer system, which is developed by using the operational one-month forecasting system by the Climate Prediction
More informationWave fluxes of equatorial Kelvin waves and QBO zonal wind forcing derived from SABER and ECMWF temperature space-time spectra
Atmos. Chem. Phys., 9, 3957 3986, 2009 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Atmospheric Chemistry and Physics Wave fluxes of equatorial Kelvin waves
More informationTraveling planetary-scale Rossby waves in the winter stratosphere: The role of tropospheric baroclinic instability
GEOPHYSICAL RESEARCH LETTERS, VOL.???, XXXX, DOI:.29/, 1 2 Traveling planetary-scale Rossby waves in the winter stratosphere: The role of tropospheric baroclinic instability Daniela I.V. Domeisen, 1 R.
More informationMomentum Flux Spectrum of Convectively Forced Internal Gravity Waves and Its Application to Gravity Wave Drag Parameterization.
JANUARY 005 S O N G A N D C H U N 107 Momentum Flux Spectrum of Convectively Forced Internal Gravity Waves and Its Application to Gravity Wave Drag Parameterization. Part I: Theory IN-SUN SONG AND HYE-YEONG
More information7 The Quasi-Biennial Oscillation (QBO)
7 The Quasi-Biennial Oscillation (QBO) (Reviewed by Baldwin et al., Rev. Geophys., 001) Previously we noted the remarkable quasi-periodic reversal of zonal winds in the tropical stratosphere, the quasi-biennial
More informationNOTES AND CORRESPONDENCE. On the Vertical Scale of Gravity Waves Excited by Localized Thermal Forcing
15 JUNE 00 NOTES AND CORRESPONDENCE 019 NOTES AND CORRESPONDENCE On the Vertical Scale of Gravity Waves Excited by Localized Thermal Forcing J. R. HOLTON, J.H.BERES, AND X. ZHOU Department of Atmospheric
More informationThe Mesosphere. Prof Nicholas Mitchell
The Mesosphere Prof Nicholas Mitchell Centre for Space, Atmospheric & Oceanic Science Department of Electronic & Electrical Engineering The University of Bath Introductory Solar System Plasma Physics Summer
More informationDevelopment of a Coupled Atmosphere-Ocean-Land General Circulation Model (GCM) at the Frontier Research Center for Global Change
Chapter 1 Atmospheric and Oceanic Simulation Development of a Coupled Atmosphere-Ocean-Land General Circulation Model (GCM) at the Frontier Research Center for Global Change Project Representative Tatsushi
More informationA Model Study of Zonal Forcing in the Equatorial Stratosphere by Convectively Induced Gravity Waves
408 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME 54 A Model Study of Zonal Forcing in the Equatorial Stratosphere by Convectively Induced Gravity Waves M. J. ALEXANDER AND J. R. HOLTON Department of Atmospheric
More informationLecture 10a: The Hadley Cell
Lecture 10a: The Hadley Cell Geoff Vallis; notes by Jim Thomas and Geoff J. Stanley June 27 In this short lecture we take a look at the general circulation of the atmosphere, and in particular the Hadley
More informationLecture 5: Atmospheric General Circulation and Climate
Lecture 5: Atmospheric General Circulation and Climate Geostrophic balance Zonal-mean circulation Transients and eddies Meridional energy transport Moist static energy Angular momentum balance Atmosphere
More informationMODEL TYPE (Adapted from COMET online NWP modules) 1. Introduction
MODEL TYPE (Adapted from COMET online NWP modules) 1. Introduction Grid point and spectral models are based on the same set of primitive equations. However, each type formulates and solves the equations
More informationATMOSPHERIC AND OCEANIC FLUID DYNAMICS
ATMOSPHERIC AND OCEANIC FLUID DYNAMICS Fundamentals and Large-scale Circulation G E O F F R E Y K. V A L L I S Princeton University, New Jersey CAMBRIDGE UNIVERSITY PRESS An asterisk indicates more advanced
More informationThe momentum budget of the QBO in WACCM. Rolando Garcia and Yaga Richter National Center for Atmospheric Research Boulder, CO
The momentum budget of the QBO in WACCM Rolando Garcia and Yaga Richter National Center for Atmospheric Research Boulder, CO a few model details Simulations use WACCM 5 at 1 horizontal resolution and 110
More informationOffline estimates and tuning of mesospheric gravity-wave forcing using Met Office analyses
Quarterly Journalof the Royal Meteorological Society Q. J. R. Meteorol. Soc. 140: 1025 1038, April 2014 DOI:10.1002/qj.2168 Offline estimates and tuning of mesospheric gravity-wave forcing using Met Office
More informationMesospheric non-migrating tides generated with planetary waves: II. Influence of gravity waves
Journal of Atmospheric and Solar-Terrestrial Physics 67 (2005) 981 991 www.elsevier.com/locate/jastp Mesospheric non-migrating tides generated with planetary waves: II. Influence of gravity waves H.G.
More informationWACCM simulations of the mean circulation linking the mesosphere and thermosphere. Anne Smith, Rolando Garcia, Dan Marsh NCAR/ACD
WACCM simulations of the mean circulation linking the mesosphere and thermosphere Anne Smith, Rolando Garcia, Dan Marsh NCAR/ACD trace species transport in the middle atmosphere wave driven mean circulation
More informationThe feature of atmospheric circulation in the extremely warm winter 2006/2007
The feature of atmospheric circulation in the extremely warm winter 2006/2007 Hiroshi Hasegawa 1, Yayoi Harada 1, Hiroshi Nakamigawa 1, Atsushi Goto 1 1 Climate Prediction Division, Japan Meteorological
More informationEffects of Nonlinearity on Convectively Forced Internal Gravity Waves: Application to a Gravity Wave Drag Parameterization
FEBRUARY 2008 C H U N E T A L. 557 Effects of Nonlinearity on Convectively Forced Internal Gravity Waves: Application to a Gravity Wave Drag Parameterization HYE-YEONG CHUN, HYUN-JOO CHOI, AND IN-SUN SONG*
More informationHigh-resolution Global Climate Modeling of Saturn s and Jupiter s tropospheric and stratospheric circulations
High-resolution Global Climate Modeling of Saturn s and Jupiter s tropospheric and stratospheric circulations Aymeric SPIGA, S. Guerlet, E. Millour, Y. Meurdesoif (LSCE/CEA), M. Indurain, S. Cabanes, M.
More information4. Atmospheric transport. Daniel J. Jacob, Atmospheric Chemistry, Harvard University, Spring 2017
4. Atmospheric transport Daniel J. Jacob, Atmospheric Chemistry, Harvard University, Spring 2017 Forces in the atmosphere: Gravity g Pressure-gradient ap = ( 1/ ρ ) dp / dx for x-direction (also y, z directions)
More informationThe Quasi-Biennial Oscillation Analysis of the Resolved Wave Forcing
The Quasi-Biennial Oscillation Analysis of the Resolved Wave Forcing Thomas Krismer, Marco Giorgetta Max Planck Institute for Meteorology Hamburg Introduction 1) The Quasi Biennial Oscillation is driven
More informationTransient and Eddy. Transient/Eddy Flux. Flux Components. Lecture 3: Weather/Disturbance. Transient: deviations from time mean Time Mean
Lecture 3: Weather/Disturbance Transients and Eddies Climate Roles Mid-Latitude Cyclones Tropical Hurricanes Mid-Ocean Eddies Transient and Eddy Transient: deviations from time mean Time Mean Eddy: deviations
More informationState of polar boreal winter stratosphere ( ) The middle and upper regions of the atmosphere are now recognized as important and
CHAPTER 3 State of polar boreal winter stratosphere (1993-2009) 3.1 Introduction The middle and upper regions of the atmosphere are now recognized as important and sensitive indicators of the polar middle
More informationINTERNAL GRAVITY WAVES
INTERNAL GRAVITY WAVES B. R. Sutherland Departments of Physics and of Earth&Atmospheric Sciences University of Alberta Contents Preface List of Tables vii xi 1 Stratified Fluids and Waves 1 1.1 Introduction
More informationWhat kind of stratospheric sudden warming propagates to the troposphere?
What kind of stratospheric sudden warming propagates to the troposphere? Ken I. Nakagawa 1, and Koji Yamazaki 2 1 Sapporo District Meteorological Observatory, Japan Meteorological Agency Kita-2, Nishi-18,
More informationStratospheric versus Tropospheric Control of the Strength and Structure of the Brewer Dobson Circulation
SEPTEMBER 2012 G E R B E R 2857 Stratospheric versus Tropospheric Control of the Strength and Structure of the Brewer Dobson Circulation EDWIN P. GERBER Center for Atmosphere Ocean Science, Courant Institute
More informationThe meteorology of monsoons
978--521-84799-5 - The Asian Monsoon: Causes, History and Effects 1 The meteorology of monsoons 1.1 Introduction Monsoon circulations are major features of the tropical atmosphere, which, primarily through
More informationAn Analysis of the Quasi Biennial Oscillation, Ozone and Thermal Damping. A Senior Project. presented to. the Faculty of the Physics Department
An Analysis of the Quasi Biennial Oscillation, Ozone and Thermal Damping A Senior Project presented to the Faculty of the Physics Department California Polytechnic State University, San Luis Obispo In
More informationThe dynamics of high and low pressure systems
The dynamics of high and low pressure systems Newton s second law for a parcel of air in an inertial coordinate system (a coordinate system in which the coordinate axes do not change direction and are
More informationA Simulation of the Separate Climate Effects of Middle-Atmospheric and Tropospheric CO 2 Doubling
2352 JOURNAL OF CLIMATE VOLUME 17 A Simulation of the Separate Climate Effects of Middle-Atmospheric and Tropospheric CO 2 Doubling M. SIGMOND Department of Applied Physics, Eindhoven University of Technology
More informationWinds and Global Circulation
Winds and Global Circulation Atmospheric Pressure Winds Global Wind and Pressure Patterns Oceans and Ocean Currents El Nino How is Energy Transported to its escape zones? Both atmospheric and ocean transport
More informationLecture 1. Equations of motion - Newton s second law in three dimensions. Pressure gradient + force force
Lecture 3 Lecture 1 Basic dynamics Equations of motion - Newton s second law in three dimensions Acceleration = Pressure Coriolis + gravity + friction gradient + force force This set of equations is the
More informationThe residual mean circulation in the tropical tropopause layer driven by tropical waves
1 2 The residual mean circulation in the tropical tropopause layer driven by tropical waves 3 4 David A. Ortland 5 6 7 8 NorthWest Research Associates 4118 148th Ave NE Redmond, WA 98052 ortland@nwra.com
More informationTemperature changes in the tropical tropopause layer
Temperature changes in the tropical tropopause layer Kohei Yoshida Division of Earth System Science, Graduate School of Environmental Science, Hokkaido University February 011 Abstract ⅰ Abstract Temperature
More informationGeneral Circulation of the Stratosphere and modelisation
a) Basic climatologies b) Interpretation of the dynamics with a heuristic model c) Brewer Dobson circulation d) Middle latitudes dynamics Stratospheric sudden warmings e) Equatorial dynamics Semi annual
More informationExploring Gravity Wave Dynamics, Sources, and Predictability in DeepWave
Exploring Gravity Wave Dynamics, Sources, and Predictability in DeepWave James D. Doyle 1, Stephen D. Eckermann 2, Eric Hendricks 1, Qingfang Jiang 1, P. Alex Reinecke 1, Carolyn A. Reynolds 1, David C.
More informationWRF MODEL STUDY OF TROPICAL INERTIA GRAVITY WAVES WITH COMPARISONS TO OBSERVATIONS. Stephanie Evan, Joan Alexander and Jimy Dudhia.
WRF MODEL STUDY OF TROPICAL INERTIA GRAVITY WAVES WITH COMPARISONS TO OBSERVATIONS. Stephanie Evan, Joan Alexander and Jimy Dudhia. Background Small-scale Gravity wave Inertia Gravity wave Mixed RossbyGravity
More informationEquatorial Superrotation on Tidally Locked Exoplanets
Equatorial Superrotation on Tidally Locked Exoplanets Adam P. Showman University of Arizona Lorenzo M. Polvani Columbia University Synopsis Most 3D atmospheric circulation models of tidally locked exoplanets
More informationSeasonal variation of equatorial wave momentum fluxes at Gadanki (13.5 N, 79.2 E)
Annales Geophysicae (2001) 19: 985 990 c European Geophysical Society 2001 Annales Geophysicae Seasonal variation of equatorial wave momentum fluxes at Gadanki (13.5 N, 79.2 E) M. N. Sasi and V. Deepa
More informationModeling the Downward Influence of Stratospheric Final Warming events
Modeling the Downward Influence of Stratospheric Final Warming events Lantao Sun Department of Atmospheric Sciences, University of Illinois at Urbana-Champaign Walter A. Robinson Division of Atmospheric
More informationIntroduction to Climate ~ Part I ~
2015/11/16 TCC Seminar JMA Introduction to Climate ~ Part I ~ Shuhei MAEDA (MRI/JMA) Climate Research Department Meteorological Research Institute (MRI/JMA) 1 Outline of the lecture 1. Climate System (
More informationTransient/Eddy Flux. Transient and Eddy. Flux Components. Lecture 7: Disturbance (Outline) Why transients/eddies matter to zonal and time means?
Lecture 7: Disturbance (Outline) Transients and Eddies Climate Roles Mid-Latitude Cyclones Tropical Hurricanes Mid-Ocean Eddies (From Weather & Climate) Flux Components (1) (2) (3) Three components contribute
More informationOn the energetics of mean-flow interactions with thermally dissipating gravity waves
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 112,, doi:10.1029/2006jd007908, 2007 On the energetics of mean-flow interactions with thermally dissipating gravity waves R. A. Akmaev 1 Received 10 August 2006; revised
More informationInertia-gravity waves in the mesosphere observed by the PANSY radar
Inertia-gravity waves in the mesosphere observed by the PANSY radar Ryosuke Shibuya *1, Kaoru Sato 1 and Masaki Tsutsumi 2 1 The University of Tokyo, Japan 2 National Institute of Polar Research, Japan
More informationAtmospheric Circulation
Atmospheric Circulation (WAPE: General Circulation of the Atmosphere and Variability) François Lott, flott@lmd.ens.fr http://web.lmd.jussieu.fr/~flott 1) Mean climatologies and equations of motion a)thermal,
More informationChange in Occurrence Frequency of Stratospheric Sudden Warmings. with ENSO-like SST Forcing as Simulated WACCM
Change in Occurrence Frequency of Stratospheric Sudden Warmings with ENSO-like SST Forcing as Simulated WACCM Masakazu Taguchi* and Dennis L. Hartmann Department of Atmospheric Sciences, University of
More information